日本第三代移动通信的发展

日本邮政省依据国内通信市场的发展速度和第二代移动通信系统的不足，制定了２００１年引入第三代移动通信系统的时间表，同时向ＩＴＵ提交了标准提案。在技术选择上，充分考虑ＣＤＭＡ的技术优势，选择了Ｗ－ＣＤＭＡ的空中接口方案。在核心网方面，日本选择了两种有助于后向兼容的技术。为使第三代系统顺利投入商用，几家运营公司已着手开始现场试验。

Third Generation Mobile Communications Development in Japan

In the light of the domestic telecom market development status quo and the drawbacks of the second generation mobile system, the MFT of Japan has mapped out a timetable for the introduction of the third generation mobile communications system, and submitted a proposal to the ITU. In terms of the technical options, full considerations have been taken into the advantages of the CDMA technology and the W - CDMA air interface scheme is chosen. As far as the core network is concerned, backward compatible technologies are selected. For the sake of successful commercialization of the third generation mobile system, some carriers have embarked on the field trial of the sytem.